(1) Field of the Invention
The present invention relates to display apparatus driving circuits and methods of driving display apparatuses, and particularly relates to a display apparatus driving circuit and a method of driving the display apparatus which reduce the amount of heat generated at a driving unit which drives a display panel.
(2) Description of the Related Art
A display apparatus including a display panel includes a driving unit for driving the display panel (for example, see Patent Literature 1: Japanese Patent No. 3233895). FIG. 49 illustrates the configuration of a conventional display apparatus according to Patent Literature 1. Here, the driving unit in the conventional display apparatus shall be described with reference to FIG. 49.
As illustrated in FIG. 49, the conventional display apparatus includes a display unit 5 (display panel), a source driver 6, a gate driver 7, a timing controller 8, a DC voltage conversion circuit 9, and a tone voltage generator 10. The driving unit corresponds to the gate driver 7 and the source driver 6.
The source driver 6 includes multiple output terminals, and multiple output buffers may be provided for generating voltage at the multiple output terminals. Each of the output buffers is connected to a data line, and drives the data line and the load of the display panel. Accordingly, when the source driver 6 outputs electric potential of a data signal Vdata, a charge-discharge current from a high potential voltage VDD or to a low potential voltage VSS flows to the load in the display panel. Here, since the charge-discharge current passes through an internal resistor in the output buffer provided in the source driver 6, heat is generated by the joule heating in the internal resistor.
Along with the increased definition of the display panel in recent years, the number of output buffers provided in one source driver 6 increases. As a result, the amount of heat generated at the source driver 6 increases. In order to suppress the generated heat at a certain temperature or lower, it is effective to reduce the number of the output buffers for each source driver 6 (reduce the number of output channels) and to use multiple source drivers 6, or to use a heat dissipating sheet. However, these methods increase the set cost, and thus further reduction in the generated heat of the source driver 6 is necessary.
The heat generated inside of the source driver 6 mostly comes from an output buffer unit. Accordingly, it is necessary to reduce the heat generated particularly at the output unit of the output buffer in order to reduce the amount of heat generated at the source driver 6.
As a method to prevent the increase in the amount of generated heat, a driving method performing thinned scanning (interlaced driving) depending on conditions of output images has been proposed (for example, see Patent Literature 1). In the technology disclosed in Patent Literature 1, the heat is reduced by switching from a progressive driving to the interlaced driving when it is determined that the image to be displayed is a still image, using a function in the timing controller 8 determining moving images and still images.